I get some nasty reviews about link-assistant rank tracker. They seem to sucker you in with a product with 6 months updates and then you need to pay a monthly fee of $20. Just as well I Googled around a bit!

Check out http://rankcheckerace.com/ . You can load in your keywords and it will check every day automatically and send you an email report which you can schedule. You can load up to a 1000 keywords absolutely free. Never been easier!